Oven observation door



P 1965 L. G. HOPKINS ETAL 3,208,446

OVEN OBSERVATION DOOR 3 Sheets-Sheet 1 Filed May 22, 1962 INVENTORSLeland G. Hopkins and Wesley E. Shreffler.

ATTORNEY p ,1965 L. HOPKINS Em. 3,208,446

OVEN OBSERVATION DOOR 3 Sheets-Sheet 2 Filed May 22, 1962 d Mr Ss R mflO e T P N oh E H w mm uw Y B EXIT ATTORNEY Sept 1965 L. e. HOPKINS ETAL3,208,446

OVEN OBSERVATION DOOR Filed May 22, 1962 3 Sheets-Sheet 3 @4 2 29 q I 1/& 77 I 55-5- 2| 33 2 55 35 42 F lg 3. INVENTORS Leland G. Hopkins andWesley E. Shreffler.

ATTORNEY United States Patent O 3,208,446 OVEN OBSERVATION DOOR LelandG. Hopkins and Wesley E. Shrelfler, Mansfield, Ohio, assiguiors toWestinghouse Electric Corporation, East Pittsburgh, Pa., a corporationof Pennsylvania Filed May 22, 1962, Ser. N 0. 196,641 4 Claims. (Cl.126-200) This invention relates to an observation door assembly for anoven or the like, especially such a door assembly having a pair ofspaced overlying panes of glass or other transparent material.

It is highly desirable that the door of an oven of a cooking range, forexample, should permit visual observation of the contents of the oven,and for this purpose many such doors are provided with one or more panesof glass. Such panes must be mounted securely but in such a way as toaccommodate the dimensional changes incident to heating and cooling ofthe oven. Complex assemblies that involve close manufacturing tolerancesor time-consuming manual assembling operations are inherentlyimpractical and of little use despite possible technical operability.

A primary object of the present invention is provision of an ovenobservation door having improved paneretaining means.

An object is simplification 'of the structural members of an ovenobservation door.

Another object is provision of an oven observation door presenting ashadow box aspect.

A further object is provision of an oven observation door that may bereadily assembled.

Other objects of this invention, together with means and methods forattaining the various objects, will be apparent from the followingdescription, and the accompanying diagrams, of a preferred embodiment ofthe invention.

FIG. 1 is a front elevation, partly cut away, of an observation door ofthis invention shown in closed position;

FIG. 2 is an exploded perspective view of the same door, on a somewhatsmaller scale;

FIG. 3 is a front elevation of the lower left corner of the door 'of thepreceding views, on a scale larger than that of FIG. 1;

FIG. 4 is a sectional elevation taken at IVIV on FIG. 3;

FIG. 5 is a side sectional elevation, similar to FIG. 4 but rotatedninety degrees clockwise and showing only part of the components, asduring assembly thereof, and on a smaller scale;

FIG. 6 is a detail side elevation, partly in section and greatlyenlarged, taken at VIVI on FIG. 1;

FIG. 7 is a detail side elevation, partly in section and greatlyenlarged, taken at VII-VII on FIG. 1.

In general, the objects of the present invention are accomplished, in anoven observation door, by means of peripheral frame means, an outer paneat the front and an inner pane at the rear of the frame means, marginaledge portions of the panes being overlapped by the frame means, spacermembers inside and extending along the peripheral edges of the framemeans, the spacer members being juxtaposed to the panes and overlappingopposing marginal edge portions thereof, and corner supports 10- 65sight, each corner of the frame including the junction of two of thestrip-like spacer members, the end of the flaring face of one thereofbeing angled at approximately half a right angle and overlying the endof the other, simulating a mitered joint.

FIG. 1 shows, in front elevation, partly cut away, observation door 11for an oven or the like, in closed position in surrounding cabinet 12'of appliance 13, which is shown only fragmentarily. Part of the doorassembly is cut away at the lower right, in the vicinity of handle 14,to expose certain of the interior components. Outer or front framemember 21 overlaps a marginal edge portion of outer pane 22, whichoverlies short or vertical spacer members 23 and long or horizontalspacer members 24. Inner pane 26 underlies the spacer members, as isapparent where they are cut away. Corner supports 27 (one visible inthis view) also underlie the spacer members, fitting alongside thecorners of the inner pane and inner or rear frame member 29. Latch 30,which is mounted on the rear frame member, appears in greater detail ina subsequent view.

FIG. 2 shows, in perspective and exploded, door 11 of the precedingview, completely disassembled. Handle 14, which has a pair of retainingscrews 15, appears foremost, at the lower right. Next appears outer orfront frame member 21, then outer pane 22, pair of short or verticalspacer members 23, pair of long or horizontal spacer members 24, innerpane 26, corner supports 27 (four in number), inner or rear frame member29, and pair of corner reinforcements 31, in that order. Screws 32,together with pair of pivot screws 33, surround outer frame member 21.

FIG. 3 shows, in front elevation, partly cut away and on an enlargedscale, the lower left corner of the door previously shown. Outer framemember 21 has peripheral flange extending to the rear from and adjoiningfront outline strip 36, which terminates in rearwardly sloping interioredge 37 in contact with the front face of outer pane 22. Vertical andhorizontal spacer members 23 and 24, immediately underlie the outerpane, with beveled edge 38 of the former overlapping beveled edge 39 ofthe latter. Underlying the spacer members is corner support 27, whichhas flat V-shaped body 41 lying against the interior face of rearoutline strip 46 of inner or rear frame member 29. That frame member hasperipheral flage extending to the front and terminates at the oppositeside in frontwardly sloping interior edge 47.

FIG. 3 shows that corner support 27 has flanges 42 at the outside edgesof the V and perpendicular to the plane of the body thereof, lyingagainst the interior face of peripheral flange 45 of the inner or rearframe member. The corner support also has flanges 43 at the inside edgesof the V, parallel to flanges 42 at the opposite edges. Whereas theoutside flanges extend to join one another at the apex of the cornerangle, the inside flanges do not join one another but remain spacedapart on opposite sides of a bisector (not indicated) of the cornerangle. Screws 32, one on each side of the corner extend through 0suitable unthreaded apertures in outer peripheral flange 35 and innerperipheral flange 45 and into threaded apertures in outside flanges 42of the corner support. Pivot screw 33 does likewise except that thethreaded aperture for it is in reinforcing disc 49 affixed to theinterior face of horizontal outside flange 42 of the corner support.Corner reinforcement 31, fits between the peripheral flanges of therespective frame members, along both sides of the corner and at theapex, flange 45 of the inner or rear member being recessed there toaccommodate the reinforcement, which also receives the pivot screwthrough a suitable unthreaded aperture.

FIG. 4 shows, in side sectional elevation, the corner of the door ofFIG. 3 as indicated thereon. In addition to the features mentioned inthe description of that preceding view, FIG. 4 shows particularly thecross-sectional configuration of horizontal spacer member 24 (all spacermembers 23 and 24 are similar in cross-section) and the location of itsvarious portions with respect to the panes and the corner support. Thespacer member has an asymmetrical channeled (inverted here) form,comprising oblique central or bed portion 51 joining short inner side 52at an acute angle (apex rounded here) and joining long outer side 53 atan obtuse angle. The respective sides are in contact with marginal edgeportions of the corresponding panes and terminate in inner flange 54 andouter flange 55, which are parallel to one another and perpendicular tothe faces of the panes. Inner flange 54 of the spacer member fits snuglybetween and against the peripheral edge of inner pane 26 and oneface ofinside flange 43 of the corner support, while outer flange 55 of thespacer member fits in like manner between the peripheral edge of theouter pane and a face of corner reinforcement 31.

FIGS. 1 to 4 clearly suggest the resulting flaring outward of theoblique portion of the spacer members toward the observer (not shown) atthe front or outside of the door. The overlap of beveled edge 38 ofvertical spacer member 23 upon edge 39 of spacer member 24 is visible inFIGS. 3 and 4, and it is apparent especially from the preceding viewsthat the termination of that overlapping edge on the overlying spacermember simulates a mitered joint, providing a shadow-box effect. Theresulting impression of depth and solidity to the door itself may beaided by the use of gray or other dark tinted glass or similar materialin the outer pane.

FIG. shows, largely in section similar to the last preceding view butrotated ninety degrees clockwise and on a smaller scale, the corner ofthe same door during assembly. The outer or front frame member ismissing, as are the screws. Corner support 27 appears in solid, whileouter pane 22 appears only in phantom. The corner support is in place inthe corner of the inner or rear frame member, which lies with rearoutline strip 46 horizontal and with peripheral flange 45 extendingupwardly. Inner pane 26 is in place with its marginal edge portionagainst the rear outline strip and with its peripheral edge adjacentrelatively short inside flange 43 of the corner support but spacedtherefrom by inner flange 54 of the spacer member.

FIG. 5 reveals that, in the absence of the outer pane, the acute anglebetween inner side 52 and central or bed portion 51 (solid line showingthereof) of the spacer member is appreciably (e.g., five to fifteendegrees) greater than the corresponding angle when the inner pane is inplace with its peripheral edge against outer flange 55 and with itsmarginal edge portion against outer side 53 of the spacer member, asshown in phantom (broken lines). With the outer pane in place, thespacer member bends sufficiently at the rounded apex of the mentionedacute angle to bring one face of outer side 53 of the spacer memberagainst the edge (at the top in this view) of outside flange 42 of thecorner support. Outer flange 55 of this spacer member becomes nearlycoplanar with outside flange 42 of the corner support when outer pane 22is so in place. The biasing of the respective panes apart from oneanother by the resilience of the spacer members is apparent, as is thejuxtaposing of the spacer members to the panes by the corner supports.

The assembling of the door to and beyond the intermediate stage of FIG.5 is apparent from it and the preceding views, including especially FIG.2, which shows the door entirely disassembled. It will be noted thatboth pairs of spacer members must be in place, with vertical spacermembers 23 overlapping horizontal spacer members 24 at their ends, overthe corner supports before outer pane 22 is put in place. Then outer orfront frame member 21 may be telescoped over inner or rear frame member29 and its contents, corner reinforcements 31 for pivot screws 33 beinginserted between the peripheral flanges of the respective frame membersand into the matching recesses of the inner frame member at the time ofthe telescoping step. Insertion of screws 32 through the aperturesprovided in the peripheral flanges of the frame members (and in thecorner reinforcements at the pivot locations) and into the alignedthreaded apertures in corner supports 27 secures all the componentstogether, retaining the panes firmly in place without undue stress. ofcourse, pivot screws 33 are inserted independently, as are screws 15 forthe handle.

FIG. 6 shows, in side elevation, on an enlarged scale and partly insection, latch 30 of the door in the closed position shown in FIG. 1. Aportion of cabinet 12 underlying rear outline strip 46 of inner or rearframe member 29 carries perpendicular prong 61 in a suitable aperture.Latch 30 comprises frame 63, which is carried in a suitable aperturecovered by attached facing ring 64, and which itself carries grippingmeans 65 attached to the frame by pins 66. The perpendicular prongextends through the facing ring and the underlying aperture into theframe of the latch where it is gripped from opposite sides by thegripping means sufficiently tightly to keep the door closed except whenit is opened manually by means of handle 14.

FIG. 7, another enlarged detail view in side sectional elevation, showsnut support '71, which is affixed to the interior face of peripheralflange 45 of inner or rear frame member 29 to receive one of screws 15for handle 14 of the door. Housing 72 thereof surrounds nut 70 fromopposite sides and terminates in pair of ears 73, which extend throughan aperture formed in embossed portion 74 of the flange and bend outwardfrom one another to grip that portion of the flange. The other one ofscrews 15 of the handle threads into corner support 29, as previouslyshown. Not shown is the pivot means that, as part of the surroundingcabinet, receives and supports pair of pivot screws 32 and 33 at theleft on upper and lower outside edges of peripheral flange 35 of outeror front frame member 21. These and the fastening means of FIGS. 6 and 7are not claimed as part of the present invention, for other suitableconventional fastening means could be substituted, but their descriptionis included to some extent as an aid to an understanding of the doorassembly as such.

Modifications also may be made in the illustrated and describedpreferred embodiment of the door without involving a departure from theclaimed structure and while retaining some or all of the advantages andbenefits of the present invention. Certain of those advantages andbenefits have been mentioned above, and others will hecome apparent andaccrue to those who undertake to practice the invention as claimed.

What is claimed is:

1. In an oven observation door having a peripheral polygonal frame andhaving an outer pane and a parallel inner pane so framed thereby thatthe sight of the outer pane overlies the sight of the inner pane,improved means for locating the panes in fixed relation to one anotherwithin the frame and comprising strip-like spacer members locatedbetween the panes and adjacent thereto and to the peripheral polygonalframe, thereby defining the sights of the respective panes, with theexposed faces of the spacer members flaring outwardly from the innerpane to the outer pane, thus rendering the outer sight larger than theinner sight, each corner of the frame including the junction of two ofthe strip-like spacer members, the end of the flaring face of onethereof being angled at approximately half the angle defined by said twostrip-like spacer members and overlying the end of the other, simulatinga mitered joint, and corner supports located between the frame and thespacer members and secured to the frame, each corner of the frame havingone of the corner supports secured thereto, the corner support extendingadjacent the peripheral edge of at least one of the panes along bothsides of the corner and being separated therefrom by the spacer members,and wherein at each corner each of the two spacer members at that cornerhas a marginal edge portion thereof contiguous with the peripheral edgeof the inner pane and has a marginal edge portion thereof contiguouswith the peripheral edge of the outer pane, and the corner support hasflanges adjacent and parallel to the respective marginal edge portionsof the respective spacer members.

2. The apparatus of claim 1 wherein at each corner the flanges of thecorner support adjacent and paralleling the spacer marginal edgeportions contiguous with the peripheral edge of the outer pane aresubstantially coplanar therewith and are contiguous with perpendicularlyadjoining portions of the respective spacer members.

3. The apparatus of claim 1 wherein at each corner the flanges of thecorner support adjacent and paralleling the spacer marginal edgeportions contiguous with the peripheral edge of the inner pane arecontiguous with one face of those marginal edge portions, the oppositeface thereof being contiguous with the peripheral edge of the innerpane.

4. Oven obsrevation door assembly comprising a hollow rectangular boxframe open along its inner edge and having telescoping outer and innerframe pieces;

an inner pane covering the sight of the inner frame piece with theperipheral edges of the pane overlapping the interior edge but spacedinside the peripheral edge of the frame piece;

corner supports, each having a V-shaped body, as viewed perpendicularlyto the pane, with flanges extending perpendicular to the body along bothouter and inner edges of the V, the outer flanges being located adjacentthe interior face of the peripheral portion of the inner frame piece,the inner flanges being located adjacent the peripheral edge of the panealongside both sides and clear of the apex of a corner of the frame andbeing smaller in lateral and perpendicular extent than the outerflanges;

spacer members having parallel outer and inner flanges and anintermediate channel interconnecting to the respective flanges at rightangles thereto and having an acute angle and an obtuse angle at thejunction of the channel bed with opposite side portions of the channel,the inner flange of each spacer member being located between theperipheral edge of the inner pane and the inner flanges of the cornersupports, the outer flange of each spacer member being located adjacentthe interior face of the peripheral edge of the inner frame piece, onepair of opposing spacer members overlying at their ends the ends of theother pair of opposing spacer members, the overlying ends being mitered;and

an outer pane covering the sight formed by the two pairs of spacermembers, the outer frame piece telescopically enclosing the inner framepiece, with the other mentioned elements intervening, and overlappingthe peripheral edge of the second pane; and

fastening means for retaining the outer and inner box frame pieces soassembled and for securing the corner supports thereto.

References Cited by the Examiner UNITED STATES PATENTS 1,968,890 8/34Hulf 18936 1,994,022 3/35 Huff 189-36 2,173,664 9/39 Shutts 126-200 X2,513,202 1/50 Reeves 20S6.5 2,536,956 l/Sl Reeves 126-200 2,810,46010/57 Winnan 189-76 3,034,612 5/62 Jourdan 18936 JAMES W. WESTHAVER,Primary Examiner. FREDERICK L. MATTESON, IR., Examiner.

1. IN A OVEN OBSERVATION DOOR HAVING A PERIPHERAL POLYGONAL FRAME ANDHAVING AN OUTER PANE AND A PARALLEL INNER PANE SO FRAMED THEREBY THATTHE SIGHT OF THE OUTER PANE OVERLIES THE SIGHT OF THE INNER PANE,IMPROVED MEANS FOR LOCATING THE PANES IN FIXED RELATION TO ONE ANOTHERWITHIN THE FRAME AND COMPRISING STRIP-LIKE SPACER MEMBERS LOCATEDBETWEEN THE PANES AND ADJACENT THERETO AND TO THE PERIPHERAL POLYGONALFRAME, THEREBY DEFINING THE SIGHTS OF THE RESPECTIVE PANES, WITH THEEXPOSED FACES OF THE SPACER MEMBERS FLARING OUTWARDLY FROM THE INNERPANE TO THE OUTER PANE, THUS RENDERING THE OUTER SIGHT LARGER THAN THEINNER SIGHT, EACH CORNER OF THE FRAME INCLUDING THE JUNCTION OF TWO OFTHE STRIP-LIKE SPACER MEMBERS, THE END OF THE FLARING FACE OF ONETHEREOF BEING ANGLED AT APPROXIMATELY HALF THE ANGLE DEFINED BY SAID TWOSTRIP-LIKE SPACER MEMBERS AND OVERLYING THE END OF THE OTEHR, SIMULATINGA MITERED JOINT, AND CORNER SUPPORTS LOCATED BETWEEN THE FRAME AND THESPACER MEMBERS AND SECURED TO THE FRAME, EACH CORNER OF THE FRAME HAVINGONE OF THE CORNER SUPPORTS SECURED THERETO, THE CORNER SUPPORT EXTENDINGADJACENT THE PERIPHERAL EDGE OF AT LEAST